An Analysis of Axisymmetric Sheet Forming by the Shell Finite Element Method : (The Case Where Gotoh's Plastic Constitutive Equation and Fourth-Order Yield Function are Used)

抄録

An elastic-plastic finite element formulation on the basis of the shell theory is given for the analysis of axisymmetric sheet forming, such as hydraulic bulging, stretching with a rigid punch and so forth. Gotoh's plastic constitutive equation with an approximation which is a kind of vertex-hardening theory and his fourth-order yield function for a precise expression of anisotropy are used, as well as the conventional J₂-flow theory. Several numerical examples are presented with the aid of a newly developed computer program in which isoparametric finite elements are used in order to conserve the continuity of the displacement and slope across the element boundaries. Several effects of the X-value and the vertex, as well as the conventional γ^^--and n-value, on the deformation of the shell are demonstrated.